If you've ever looked at your rooted Dell Streak and wished Ubuntu was staring back at you from behind the screen instead of Android, then it's probably a good idea to make friends with pat.plus at the MoDaCo forum.
He/She has put up a simple tutorial over there on how to get Ubuntu Mobile "running piggyback" on the Streak (think "virtual machine") and is currently working on a native port of the Linux distro. The latter task is proving difficult thus far, partially due to the lack of bootloaders, so typing a few simple commands in ADB on your computer or a terminal emulator on your Streak is the way to go at the moment.
Getting Ubuntu running on an Android device using this method (or a similar one) is fairly common—it was originally done on the Nexus One last year and has also been done on the HTC EVO, for example—but since there aren't a whole lot of Streak devs out there, it's great to see it being done on the Streak too. Not many people have attempted a native install, but then again, not many people have an Android phone with a 5-inch screen!
If you want to check out Ubuntu on your Streak and/or can lend a hand in fixing bugs or furthering development, you'll find the full set of instructions and the folks who are talking about it at the link below.
[Android @ MoDaCo]